1. Field of the Invention
This invention relates to a control system for controlling the operation of an air conditioning system, and more particularly to a load management control system for reducing air conditioning load during peak periods.
2. Description of the Art
The control of temperature in enclosed areas such as residential and commercial buildings is important for comfort of the inhabitants as well as for efficiency. Energy considerations become important when the outside temperature substantially exceeds an indoor temperature set point. In conventional air conditioning systems, automatic controls maintain cooling levels in a selected range. Most thermostatic controls permit the user to set a prescribed temperature above which the system will energize to cool the building. However, when the outdoor temperature greatly exceeds the indoor temperature set point, a substantial energy load is required to maintain the indoor temperature. As a result, excessive cooling of the building adversely effects the physical condition of building occupants, and energy is wasted since the air conditioner is operated to provide an energy load in excess of that required to maintain a comfortable interior temperature.
Prior systems have attempted to control the indoor temperature based upon the outdoor temperature. U.S. Pat. No. 4,289,272 discloses a temperature control apparatus which operates by calculating a desired indoor temperature using a predetermined linear function of outdoor temperature.
U.S. Pat. No. 4,089,462 discloses a temperature control system for shifting the indoor temperature set point in accordance with outdoor temperature. Heating and cooling input to a room of a building is controlled based upon the outdoor temperature and a K-Factor, to maintain a constant indoor temperature. However, careful analysis of the dwelling heat transfer ability is required for such control.
While the control systems described in the above references provide a significant improvement in air conditioning systems, these systems require either complicated algorithms or a study of particular building characteristics to facilitate temperature control.
It would be desirable, therefore, to provide a simple and more effective means of controlling the load requirements for an air conditioning system based upon a difference between indoor and outdoor temperature.